Lux Junior 2017 - Startseite TU Ilmenau...3 Result 25.09.2017 Seite 14 Part 1: Analysis of Age and Color Matching Function CMF Young subjects (60

Johannes Michl – Lux Junior 2017, Dörnfeld

www.tu-ilmenau.de/lichttechnik25.09.2017 Seite 1

Lux Junior 2017Investigation of color matching functions for prediction of

perception of luminous color differencesdepending on age and luminous color in the surrounding

Untersuchung von Spektralwertfunktionen für die Beschreibung der Wahrnehmung von Lichtfarbenunterschieden in

Abhängigkeit von Alter und Umfeldlichtfarbe

Johannes Michl

10.09.2017


www.tu-ilmenau.de/lichttechnik

1 Introduction – Why did we do this?

25.09.2017 Seite 2



1 Introduction

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What are Color Matching Functions (CMFs)?

Image Copyrights:Eye: askabilogist.asu.eduLED: osram.com

Color Effect

Color Coordinate

Light Spectrum Color Matching Functions



Points of criticism: Difference in lighting technology then and now Low number of subjects Testing conditions do not match current applications Further validity of this standard is questionable

1 Introduction

25.09.2017 Seite 4

Problem 1: LED-Binning

LED production process can‘t behandled precise enough: Binning (=sorting) of productionnecessary according to colorcoordinate

Binning is based on the insights of MacAdam (1940s) and thestandardized color matching functions (CMF) CIE1931:

[osram.com]



1 Einführung

Research from POLSTER: visual similar lights show partlyhigh color coordinates distancewith CIE1931 CMFs

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Problem 2: Color Space Failures

[Pol14]

Development of adjusted CMFs: 2006-TUIL-2º bzw. 2006-TUIL-10º

∆u‘v‘=0,0165



1 Introduction

Calculation of age-dependentCMFs described in: CIE170-1:2006 und CIE170-2:2015

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Problem 3: Age-dependent yellowing of eye lens

[Hün09]

[Ler80]

Age-dependentyellowing of eye lense

Age-dependent transmittance ofeye lens



2 Study – What did we do?

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2 Study

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∆u‘v‘ ∆u‘v‘ ∆u‘v‘

u‘

v‘

colorprocessingin brain

380 nm 580 nm 780 nm

380 480 580 680 780

Color Matching Functions

• CIE1931• CIE2006• 2006-TUIL

lighted rating areas

correlation?

Method of Study

LED1 LED2

Spectra>60 years <35 years

lighted surrounding

no noticeable color difference

just noticeable color difference

small color difference

big color difference

very big color difference



2 Study

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Setup of Study

• rating area: 30 cm x 30 cm each• 10 different LED spectra (CCT=3.500K)• distance subject to rating area: 1,7m (-> field size: 10º)

10º

1.7

m

1 2surrounding: 200 cd/m²

rating area800cd/m²



2 Study

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Measurement of SetupLuminance of Lightbox

650cd/m²

890cd/m²

800cd/m²

90cd/m²

73%

Color coordinates of the10 lightboxes



2 Study

• Calculation of color coordinatedistance for various CMFs:

– Current standard: CIE1931 und CIE1964– Newest recommendation of CIE: CIE2006-2º and 10º acc. to CIE170-2:2015– Development of POLSTER: 2006-TUIL-2º and 10º– Age-adjusted CMFs acc. to CIE170-1:2006

(CIE2006-10º-A70, 2006-TUIL-10º-A70)

• Selection of suitable test combinations

23 different test combinations

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Selection of Test Combinations∆ ² ²

small: ∆u‘v‘ < 0,0021 medium big: ∆u‘v‘ > 0,0040

CIE1931 CIE2006 2° 2006‐TUIL‐2° CIE1964 CIE2006 10° CIE2006 10°A60

2006‐TUIL‐10°

2006‐TUIL‐10° A60

0,0034 0,0025 0,0053 0,0002 0,0004 0,0036 0,0046 0,0007



3 Result – What did we find out?

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3 Result

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Part 1: Analysis of Age and Color Matching Function

Young subjects(<35 years, N=41)

Older subjects(>60 years, N=39)

All subjectsN=80



3 Result

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Part 1: Analysis of Age and Color Matching Function

CMF Young subjects(<35 years, N=41)

Older subjects(>60 years, N=39)

All subjectsN=80

no correlation low correlation medium correlation

high correlation very high correlation

Comparisment of Coefficient of Determination (R²)



3 Result

25.09.2017 Seite 15

Part 2: Analysis of the Effect of the SorroundingColor



3 Result

• Perception of luminous color differences is age-dependent• This effect can be described by age-dependet CMFs• For this study the age-dependent version of CMF 2006-TUIL-10º

showed the best correlation• Use of current standard CIE1931 is not sufficient• The surrounding color has no siginificant effect on the rating of

luminous color differences

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Summary

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Thank you!



Documents

Lux Junior 2017 - Startseite TU Ilmenau...3 Result 25.09.2017 Seite 14 Part 1: Analysis of Age and Color Matching Function CMF Young subjects (60